Mix the softened cream cheese and Zest Sauce until combined. Bake the sliced polenta on a greased cookie sheet, at 375* for 10-15 min. until golden brown, turning halfway through. Allow the polenta squares to cool. Spread the cream cheese/Zest Sauce mixture on each square. Top with roast beef, caramelized onion and a sprinkle of zest sauce. Garnish with a parsley leaf.